Call re-routing upon cell phone docking

ABSTRACT

A method and apparatus are provided for call setup in a communication network that comprises at least one mobile station to facilitate the hand-off of a wireless headset from a mobile station that has been docked to a landline base unit that includes a radio front end operable to communicate with the wireless headset. Generally, the embodiments of the invention include establishing a first voice path through at least one switching element between a calling party and a called party in a communication network where at least one of the called and calling parties is communicating with the mobile station or, more generally, with a wireless telephone. Thereafter, a first wireless headset communication link is established between the wireless telephone and the wireless headset unit.

CROSS REFERENCES TO RELATED APPLICATIONS

The present U.S. Utility Patent Application claims priority pursuant to35 U.S.C. § 119(e) to the following U.S. Provisional Patent Applicationswhich are hereby incorporated herein by reference in their entirety andmade part of the present U.S. Utility Patent Application for allpurposes:

-   -   1. U.S. Provisional Application Ser. No. 60/646,254, entitled        “Call Re-routing Upon Cell Phone Docking,” filed Jan. 24, 2005,        expired.

BACKGROUND

1. Technical Field

The present invention relates to wireless communications and, moreparticularly, to cellular wireless communication systems and a method ofcall setup therefor.

2. Related Art

Communication systems are known to support wireless and wire linedcommunications between wireless and/or wire lined communication devices.Such communication systems range from national and/or internationalcellular telephone systems to the Internet to point-to-point in-homewireless networks. Each type of communication system is constructed, andhence operates, in accordance with one or more communication standards.For instance, wireless communication systems may operate in accordancewith one or more standards, including, but not limited to, IEEE 802.11,Bluetooth, advanced mobile phone services (AMPS), digital AMPS, globalsystem for mobile communications (GSM), code division multiple access(CDMA), local multi-point distribution systems (LMDS),multi-channel-multi-point distribution systems (MMDS), and/or variationsthereof.

Depending on the type of wireless communication system, a wirelesscommunication device, such as a cellular telephone, two-way radio,personal digital assistant (PDA), personal computer (PC), laptopcomputer, home entertainment equipment, etc., communicates directly orindirectly with other wireless communication devices. For directcommunications (also known as point-to-point communications), theparticipating wireless communication devices tune their receivers andtransmitters to the same channel or channels (e.g., one of a pluralityof radio frequency (RF) carriers of the wireless communication system)and communicate over that channel(s). For indirect wirelesscommunications, each wireless communication device communicates directlywith an associated base station (e.g., for cellular services) and/or anassociated access point (e.g., for an in-home or in-building wirelessnetwork) via an assigned channel. To complete a communication connectionbetween the wireless communication devices, the associated base stationsand/or associated access points communicate with each other directly,via a system controller, via a public switch telephone network (PSTN),via the Internet, and/or via some other wide area network.

Each wireless communication device includes a built-in radio transceiver(i.e., receiver and transmitter) or is coupled to an associated radiotransceiver (e.g., a station for in-home and/or in-building wirelesscommunication networks, RF modem, etc.). As is known, the transmitterincludes a data modulation stage, one or more intermediate frequencystages, and a power amplifier stage. The data modulation stage convertsraw data into baseband signals in accordance with the particularwireless communication standard. The one or more intermediate frequencystages mix the baseband signals with one or more local oscillations toproduce RF signals. The power amplifier stage amplifies the RF signalsprior to transmission via an antenna.

Local Area Networks (wired LANS), e.g., Ethernets, supportcommunications between networked computers and other devices within aserviced area. These wired LANs often link serviced devices to Wide AreaNetworks and the Internet. Each of these networks is generallyconsidered a “wired” network, even though some of these networks, e.g.,the PSTN, may include some transmission paths that are serviced bywireless links.

Wireless networks have come into existence more recently. Examplesinclude cellular telephone networks, wireless LANs (WLANs), andsatellite communication networks. Common forms of WLANs, such as IEEE802.11(a) networks, IEEE 802.11(b) networks, and IEEE 802.11(g)networks, are referred to jointly as “IEEE 802.11 networks.” In atypical IEEE 802.11 network, a wired backbone couples to a plurality ofwireless Access Points (APs), each of which supports wirelesscommunications with computers and other wireless terminals that includecompatible wireless interfaces within a serviced area. The wiredbackbone couples the APs of the IEEE 802.11 network to other networks,both wired and wireless, and allows serviced wireless terminals tocommunicate with devices external to the IEEE 802.11 network. Devicesthat operate consistently with an IEEE 802.11 protocol may also supportad-hoc networking in which wireless terminals communicate directly toone another without the presence of an AP.

WLANs now also support voice communications via wireless voiceterminals. In supporting the wireless voice terminals, the WLAN works incooperation with a Private Branch Exchange (PBX) to interface the WLANwith the PSTN. A serviced call is routed between the PSTN and a servicedwireless voice terminal via the PBX and the WLAN. In addition to WLANs,personal area networks (PANs) are gaining in popularity. Initiallyconceived to reduce cabling between devices, PAN technologies, and morespecifically, Bluetooth based PANs or piconets, are adding yet anotherwireless layer to existing networks. For example, Bluetooth radios maybe embedded in wireless headsets, printers, wireless keyboards, etc., tocommunicatively couple a peripheral device to a network component. Forexample, Bluetooth may be used to wirelessly couple a wireless headsetto a handset that may be used in either a cellular network or merely ina PSTN based cordless phone. One problem not addressed in the prior art,however, relates to handoff of a wireless handset between cellularnetworks and especially the handoff of a wireless headset that iscommunicatively coupled to the wireless handset engaged in a cellularcall to a specified landline docking station base unit that is operableto conduct telephone calls over the PSTN, and more particularly, asystem and method for such handoff when a mobile station activelyengaged in a call is docked in a docking station.

SUMMARY OF THE INVENTION

A method and apparatus are provided for call setup in a communicationnetwork that comprises at least one mobile station to facilitate thehand-off of a wireless headset from a mobile station that has beendocked to a landline base unit that includes a radio front end operableto communicate with the wireless headset. Generally, the embodiments ofthe invention include establishing a first voice path through at leastone switching element between a calling party and a called party in acommunication network where at least one of the called and callingparties is communicating with the mobile station or, more generally,with a wireless telephone. Thereafter, a first wireless headsetcommunication link is established between the wireless telephone and thewireless headset unit. While the call is active, once the wirelesstelephone is docked, the various embodiments of the invention includetransmitting call setup signals to the switching element to switch froma first to a second voice path. In one embodiment of the invention, themobile station is operable to determine to generate the call setupsignaling to transfer voice paths. In an alternate embodiment of theinvention, the wireless headset is operable to instruct the wirelesstelephone to initiate the transfer upon receiving an indication that asecond wireless headset communication link has been established. In yetanother embodiment of the invention, the landline base unit is operableto determine when the voice path should be switched from the first tothe second voice path and to generate signaling to the at least oneswitching element to prompt the transition from the first voice path tothe second voice path.

In an embodiment of the invention in which the wireless headset isoperable to communicate according to a Bluetooth protocol, the wirelessheadset is further operable to, as master of a Bluetooth piconet, todetermine when a parallel voice path should be formed, when switchingshould occur, and when a first wireless headset communication linkshould be terminated after switching to the second voice path. In anembodiment of the invention where the wireless headset does not includesuch logic, the wireless headset is operable to switch master/slaveroles with one of the wireless telephone or the landline base unit, andmore specifically, to the landline base unit, to facilitate the landlinebase unit determining when to initiate switching and when to drop thefirst wireless headset communication link.

Other aspects of the present invention will become apparent with furtherreference to the drawings and specification, which follow.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention can be obtained when thefollowing detailed description of the preferred embodiment is consideredwith the following drawings, in which:

FIG. 1 is a functional block diagram illustrating a communication systemthat includes circuit devices and network elements and operation thereofaccording to one embodiment of the invention;

FIG. 2 is a schematic block diagram illustrating a wirelesscommunication host device and an associated radio;

FIG. 3 is a partial communication network that illustrates oneembodiment of the present invention;

FIG. 4 is a functional block diagram of a mobile station and a wirelessheadset according to one embodiment of the present invention;

FIG. 5 is a signal sequence diagram that illustrates operation accordingto one embodiment of the present invention;

FIG. 6 is a flowchart illustrating a method according to one embodimentof the present invention; and

FIG. 7 is a flowchart illustrating one embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram illustrating a communication systemthat includes circuit devices and network elements and operation thereofaccording to one embodiment of the invention. More specifically, aplurality of network service areas 04, 06 and 08 are a part of a network10. Network 10 includes a plurality of base stations or access points(APs) 12-16, a plurality of wireless communication devices 18-32 and anetwork hardware component 34. The wireless communication devices 18-32may be laptop computers 18 and 26, personal digital assistants 20 and30, personal computers 24 and 32 and/or cellular telephones 22 and 28.The details of the wireless communication devices will be described ingreater detail with reference to FIGS. 2-7.

The base stations or APs 12-16 are operably coupled to the networkhardware component 34 via local area network (LAN) connections 36, 38and 40. The network hardware component 34, which may be a router,switch, bridge, modem, system controller, etc., provides a wide areanetwork connection 42 for the communication system 10 to an externalnetwork element. Each of the base stations or access points 12-16 has anassociated antenna or antenna array to communicate with the wirelesscommunication devices in its area. Typically, the wireless communicationdevices 18-32 register with the particular base station or access points12-16 to receive services from the communication system 10. For directconnections (i.e., point-to-point communications), wirelesscommunication devices communicate directly via an allocated channel.

Typically, base stations are used for cellular telephone systems andlike-type systems, while access points are used for in-home orin-building wireless networks. Regardless of the particular type ofcommunication system, each wireless communication device includes abuilt-in radio and/or is coupled to a radio.

FIG. 2 is a schematic block diagram illustrating a wirelesscommunication device 18-32 as a host device and an associated radio 60.For cellular telephone hosts, radio 60 is a built-in component. Forpersonal digital assistants hosts, laptop hosts, and/or personalcomputer hosts, the radio 60 may be built-in or an externally coupledcomponent.

As illustrated, the host wireless communication device 18-32 includes aprocessing module 50, a memory 52, a radio interface 54, an inputinterface 58 and an output interface 56. Processing module 50 and memory52 execute the corresponding instructions that are typically done by thehost device. For example, for a cellular telephone host device,processing module 50 performs the corresponding communication functionsin accordance with a particular cellular telephone standard.

Radio interface 54 allows data to be received from and sent to radio 60.For data received from radio 60 (e.g., inbound data), radio interface 54provides the data to processing module 50 for further processing and/orrouting to output interface 56. Output interface 56 providesconnectivity to an output device, such as a display, monitor, speakers,etc., such that the received data may be displayed. Radio interface 54also provides data from processing module 50 to radio 60. Processingmodule 50 may receive the outbound data from an input device, such as akeyboard, keypad, microphone, etc., via input interface 58 or generatethe data itself. For data received via input interface 58, processingmodule 50 may perform a corresponding host function on the data and/orroute it to radio 60 via radio interface 54.

Radio 60 includes a host interface 62, a digital receiver processingmodule 64, an analog-to-digital converter 66, a filtering/gain module68, a down-conversion module 70, a low noise amplifier 72, a receiverfilter module 71, a transmitter/receiver (TX/RX) switch module 73, alocal oscillation module 74, a memory 75, a digital transmitterprocessing module 76, a digital-to-analog converter 78, a filtering/gainmodule 80, an up-conversion module 82, a power amplifier (PA) 84, atransmitter filter module 85, and an antenna 86. The antenna 86 isshared by the transmit and receive paths as regulated by the TX/RXswitch module 73. The antenna implementation will depend on theparticular standard to which the wireless communication device iscompliant.

Digital receiver processing module 64 and digital transmitter processingmodule 76, in combination with operational instructions stored in memory75, execute digital receiver functions and digital transmitterfunctions, respectively. The digital receiver functions include, but arenot limited to, demodulation, constellation demapping, decoding, and/ordescrambling. The digital transmitter functions include, but are notlimited to, scrambling, encoding, constellation mapping, and/ormodulation. Digital receiver and transmitter processing modules 64 and76, respectively, may be implemented using a shared processing device,individual processing devices, or a plurality of processing devices.Such a processing device may be a microprocessor, micro-controller,digital signal processor, microcomputer, central processing unit, fieldprogrammable gate array, programmable logic device, state machine, logiccircuitry, analog circuitry, digital circuitry, and/or any device thatmanipulates signals (analog and/or digital) based on operationalinstructions.

Memory 75 may be a single memory device or a plurality of memorydevices. Such a memory device may be a read-only memory, random accessmemory, volatile memory, non-volatile memory, static memory, dynamicmemory, flash memory, and/or any device that stores digital information.Note that when digital receiver processing module 64 and/or digitaltransmitter processing module 76 implements one or more of its functionsvia a state machine, analog circuitry, digital circuitry, and/or logiccircuitry, the memory storing the corresponding operational instructionsis embedded with the circuitry comprising the state machine, analogcircuitry, digital circuitry, and/or logic circuitry. Memory 75 stores,and digital receiver processing module 64 and/or digital transmitterprocessing module 76 executes, operational instructions corresponding toat least some of the functions illustrated herein.

In operation, radio 60 receives outbound data 94 from host wirelesscommunication device 18-32 via host interface 62. Host interface 62routes outbound data 94 to digital transmitter processing module 76,which processes outbound data 94 in accordance with a particularwireless communication standard (e.g., IEEE 802.11a, IEEE 802.11b,Bluetooth, etc.) to produce digital transmission formatted data 96.Digital transmission formatted data 96 will be a digital baseband signalor a digital low IF signal, where the low IF typically will be in thefrequency range of 100 kilohertz to a few megahertz.

Digital-to-analog converter 78 converts digital transmission formatteddata 96 from the digital domain to the analog domain. Filtering/gainmodule 80 filters and/or adjusts the gain of the analog baseband signalprior to providing it to up-conversion module 82. Up-conversion module82 directly converts the analog baseband signal, or low IF signal, intoan RF signal based on a transmitter local oscillation 83 provided bylocal oscillation module 74. Power amplifier 84 amplifies the RF signalto produce an outbound RF signal 98, which is filtered by transmitterfilter module 85. The antenna 86 transmits outbound RF signal 98 to atargeted device such as a base station, an access point and/or anotherwireless communication device.

Radio 60 also receives an inbound RF signal 88 via antenna 86, which wastransmitted by a base station, an access point, or another wirelesscommunication device. The antenna 86 provides inbound RF signal 88 toreceiver filter module 71 via TX/RX switch module 73, where RX filtermodule 71 bandpass filters inbound RF signal 88. The RX filter module 71provides the filtered RF signal to low noise amplifier 72, whichamplifies inbound RF signal 88 to produce an amplified inbound RFsignal. Low noise amplifier 72 provides the amplified inbound RF signalto down-conversion module 70, which directly converts the amplifiedinbound RF signal into an inbound low IF signal or baseband signal basedon a receiver local oscillation 81 provided by local oscillation module74. Down-conversion module 70 provides the inbound low IF signal orbaseband signal to filtering/gain module 68. Filtering/gain module 68may be implemented in accordance with the teachings of the presentinvention to filter and/or attenuate the inbound low IF signal or theinbound baseband signal to produce a filtered inbound signal.

Analog-to-digital converter 66 converts the filtered inbound signal fromthe analog domain to the digital domain to produce digital receptionformatted data 90. Digital receiver processing module 64 decodes,descrambles, demaps, and/or demodulates digital reception formatted data90 to recapture inbound data 92 in accordance with the particularwireless communication standard being implemented by radio 60. Hostinterface 62 provides the recaptured inbound data 92 to the hostwireless communication device 18-32 via radio interface 54.

As one of average skill in the art will appreciate, the wirelesscommunication device of FIG. 2 may be implemented using one or moreintegrated circuits. For example, the host device may be implemented ona first integrated circuit, while digital receiver processing module 64,digital transmitter processing module 76 and memory 75 may beimplemented on a second integrated circuit, and the remaining componentsof radio 60, less antenna 86, may be implemented on a third integratedcircuit. As an alternate example, radio 60 may be implemented on asingle integrated circuit. As yet another example, processing module 50of host device 18-32 and digital receiver processing module 64 anddigital transmitter processing module 76 of radio 60 may be a commonprocessing device implemented on a single integrated circuit.

Memory 52 and memory 75 may be implemented on a single integratedcircuit and/or on the same integrated circuit as the common processingmodules of processing module 50, digital receiver processing module 64,and digital transmitter processing module 76. As will be described, itis important that accurate oscillation signals are provided to mixersand conversion modules. A source of oscillation error is noise coupledinto oscillation circuitry through integrated circuitry biasingcircuitry. One embodiment of the present invention reduces the noise byproviding a selectable pole low pass filter in current mirror devicesformed within the one or more integrated circuits.

The wireless communication device of FIG. 2 is one that may beimplemented to include either a direct conversion from RF to basebandand baseband to RF or for a conversion by way of a low intermediatefrequency. In either implementation, however, for up-conversion module82 and down-conversion module 70, it is required to provide accuratefrequency conversion. For down-conversion module 70 and up-conversionmodule 82 to accurately mix a signal, however, it is important thatlocal oscillation module 74 provide an accurate local oscillation signalfor mixing with the baseband or RF by up-conversion module 82 anddown-conversion module 70, respectively.

Accordingly, local oscillation module 74 includes circuitry foradjusting an output frequency of a local oscillation signal providedtherefrom. Local oscillation module 74 receives a frequency correctioninput that it uses to adjust an output local oscillation signal toproduce a frequency corrected local oscillation signal output. Whilelocal oscillation module 74, up-conversion module 82 and down-conversionmodule 70 are implemented to perform direct conversion between basebandand RF, it is understood that the principles herein may also be appliedreadily to systems that implement an intermediate frequency conversionstep at a low intermediate frequency.

FIG. 3 is a partial communication network that illustrates oneembodiment of the present invention. A partial communication network 100includes a switching element that routes control and voice signalingthrough the partial communication network 100. In the describedembodiment, the switching element comprises a mobile switching center(MSC) 102. MSC 102 is further coupled to a base station controller (BSC)104 that controls communications through a base station transceiversystem (BTS) 106. BTS 106 transmits and receives wireless communicationsignals with cellular mobile stations, such as mobile station (MS) 108.Any one of the aforementioned cellular technologies may be representedherein by MSC 102, BSC 104, BTS 106 or MS 108. In the specific example,BTS 106 and MS 108 exchange communication signals over a communicationchannel 110.

MSC 102 is further operatively coupled to a public switched telephonenetwork (PSTN) 112 that carries voice and control signaling for thelandline telephone networks. It is understood that PSTN 112 includestraditional telephone networks, as well as newer SS7-based telephonenetworks that utilize a signaling plane as well as a voice plane. In thedescribed example, PSTN 112 is further coupled to a plurality of PSTNlandline phones (not shown), as well as to a docking station base unit114. Docking station base unit 114 includes an internal modem and isoperable to establish a telephone connection through PSTN 112. Dockingstation base unit 114 is operable to receive and charge MS 108.

In the described embodiment of the invention, docking station base unit114 includes a radio front end for engaging in wireless communicationswith wireless headsets. In one embodiment of the invention, the radiofront end is operable to communicate according to a Bluetooth protocolwith a Bluetooth-enabled wireless headset. As shown herein, dockingstation base unit 114 is operable to communicate with a wireless headset116 over a wireless headset communication link 118. As may further beseen, wireless headset 116 is operable to communicate over a wirelessheadset communication link 120 with MS 108. As is suggested by thefigure, wireless headset 116 is operable to communicate over a wirelessheadset communication link 120 with MS 108 when MS 108 is mobile or whenMS 108 is docked within docking station base unit 114.

Continuing to examine FIG. 3, MSC 102 is further coupled to any one of aplurality of networks or systems to which calls may be routed, or fromwhich calls may be received. Typically, a voice path would be set upfrom an external network, to MS 108, for example, for a given call.Thus, a first voice path 122 is shown through MSC 102, BSC 104, BTS 106and communication channel 110 to MS 108. Thus, for example, if a call isreceived from an external network, shown herein as PBX/PSTN/IP 124, thenthe voice path is as described, wherein voice is routed through firstvoice path 122. PBX/PSTN/IP 124 represents, as should be understood, tobe either a private branch exchange, a public switched telephonenetwork, or an IP network having a corresponding user terminal fromwhich a call may be received. In the described embodiment of theinvention, a second voice path 126 is defined from MSC 102 through PSTN112 to docking station base unit 114. Docking station base unit 114, asdescribed before, includes circuitry for conducting calls through thePSTN, as well as a radio front end for transmitting and receiving voiceto a wireless headset, such as wireless headset 116. In operation, theinvention is operable to initially carry a call through first voice path122 and then, upon receiving an indication that MS 108 has been dockedwithin docking station base unit 114, to create a parallel call throughsecond voice path 126 to facilitate handover of the call from MS 108 todocking station base unit 114. Significantly, wireless headset 116 mustbe handed over from MS 108 to docking station base unit 114. Thus,communication signals received on the first voice path 122 that aretransmitted over wireless headset communication link 120 to wirelessheadset 116 are switched to be carried over the second voice path 126 todocking station base unit 114 and over wireless headset communicationlink 120 to wireless headset 116. Such operation is advantageous in thattypical reliability considerations, as well as economic considerations,make a public switched telephone network user terminal preferable forcarrying a call over a wireless communication link to a cell phone, suchas MS 108. As is known, a cell phone or mobile station (MS) 108 issubject to interference, thereby reducing call quality. Moreover, thereis typically an associated “per minute” cost with cell phones, while (atleast in North America) there is no per minute cost for local callsthrough the PSTN.

The various embodiments of the invention, therefore, are operable tofacilitate the handover of the wireless headset for MS 108 to dockingstation base unit 114. In one embodiment of the invention, MS 108includes the logic for effecting such handover. In another embodiment ofthe invention, wireless headset 116 includes the logic for effectingsuch handover. In the first embodiment, in which MS 108 includes thelogic for effecting such handover, the mobile station is operable, upondetermining that it has been docked within docking station base unit114, to initiate a call over communication channel 110 to BTS 106 andBSC 104, to establish the parallel call through the second voice path126. More specifically, MS 108 generates call setup signals to anassigned PSTN telephone number for docking station base unit 114.Accordingly, BSC 104 is operable to communicate with MSC 102 to route acall, and more specifically, to set up a call, through PSTN 112 todocking station base unit 114. MS 108 is also operable to initiateprocedures to add docking station base unit 114 to a wireless piconetthat includes at least wireless headset 116 and MS 108. Accordingly,wireless headset 116 is operable to transmit and receive voice signalsover a wireless headset communication link 118 while continuing tosupport the call over wireless headset communication link 120. Forexample, if MS 108 is operating as a master of the piconet that includesMS 108, wireless headset 116 and docking station base unit 114, oneembodiment of the invention includes MS 108 trading master/slave roleswith one of wireless headset 116 and docking station base unit 114. Inany embodiment, however, once wireless headset communication link 118 isestablished between wireless headset 116 and docking station base unit114, and after resources are allocated to the second voice path 126 (ifthe actual voice path has not yet been created), then MS 108 is operableto generate an indication to MSC 102 to switch from the first voice path122 to the second voice path 126. Thereafter, first voice path 122 maybe torn down and wireless headset communication link 120 may beterminated.

In an alternate embodiment of the invention, wireless headset 116 isoperable to act as a master of the piconet and to add docking stationbase unit 114 to the piconet that already includes wireless headset 116and MS 108. Accordingly, after docking station base unit 114 has beenadded to the piconet, and docking station base unit 114 produces anindication to wireless headset 116 that either the second voice path 126has been established or that resources have been allocated to secondvoice path 126, then wireless headset 116 is operable to generate asignal to prompt MSC 102 to switch from the first voice path 122 to thesecond voice path 126. Moreover, wireless headset 116 is operable todetermine whether to terminate wireless headset communication link 120with MS 108 as necessary.

FIG. 4 is a functional block diagram of a mobile station (MS) 150 and ofwireless headset 152 according to one embodiment of the presentinvention. As may be seen, MS 150 includes a processor 154 that isoperably coupled to communicate with a memory 156 over a bus 158.Additionally, processor 154 is operable to communicate with a temporarymemory 160, a first radio front end 162 and a second radio front end 164over bus 158. In the described embodiment of the invention, first radiofront end 162 is operable to communicate with a base station accordingto any one of a plurality of previously mentioned cellular protocols,including GSM, EDGE, CDMA, North American TDMA, as well as variouscellular data packet network protocols, including 1xEVDO, 1xEVDD, UMTS,etc. Second radio front end 164 is operable, in the describedembodiment, to communicate according to a Bluetooth protocol.Alternatively, second radio front end 164 is operable to communicateover any known WLAN protocol, including 802.11 standard protocols.

Wireless headset 152 also includes a processor 170 that is operable tocommunicate with a memory 172, a temporary memory 174 and a third radiofront end 176 over a bus 178. In the described embodiment, third radiofront end 176 is operable to communicate according to the Bluetoothprotocol. Generally, third radio front end 176 is operable tocommunicate with second radio front end 164. Memory 156 of MS 150, andmemory 172 of wireless headset 152, include computer instructions thatdefine operational logic as is defined herein for the respectivedevices. Thus, memory 156 of MS 150 includes routine operating logic forcellular operations through first radio front end 162 and for Bluetoothor WLAN operations through second radio front end 164 according towhether second radio front end 164 is a Bluetooth radio or WLAN radio.Similarly, memory 172 of wireless headset 152 includes computerinstructions for communicating according to the Bluetooth or WLANprotocol third radio front end 176.

In an embodiment where the mobile station controls or initiates thecreation of a parallel call path for switchover from a first voice pathto a second voice path, memory 156 further includes computerinstructions to define such operational logic as is described herein.Likewise, memory 172 of wireless headset 152 includes logic foroperation according to the various embodiments described for thewireless headset. For example, memory 172 includes logic for initiatinga parallel call from MS 150 to effectuate a switch from a first voicepath to a second voice path. Additionally, for that embodiment, memory172 defines logic for prompting MS 150 to generate a call signal to aswitching element, such as MSC 102 of FIG. 3, to cause the switchingelement to switch the voice path from the first voice path to the secondvoice path. Memory 172 further defines logic for establishing a wirelessheadset communication link with a fourth radio front end that iscompatible with second and third radio front ends 164 and 176,respectively, of a docking station, such as docking station base unit114 of FIG. 3, and, as necessary, to drop a communication link throughthe third radio front end 176 of wireless headset 152 with the secondradio front end 164 of MS 150.

FIG. 5 is a signal sequence diagram that illustrates operation accordingto one embodiment of the present invention. Referring now to FIG. 5, thesignal sequence diagram is shown between elements already describedabove, namely, switching element 102, base station controller 104,mobile station 150, wireless headset 152, PSTN 112, and docking stationbase unit 114. Switching element 102 was shown in FIG. 3 as MSC 102.Generally, however, the invention is not limited to MSCs and is operablewith any type of switching element according to a network which willswitch from a first voice path to a second voice path. Accordingly, in atraditional PSTN or cellular network, the switching element is an MSCand is operable to switch a voice bearer path from a first voice bearerpath to a second voice bearer path. The reference herein to voice path,however, is intended to be broader than voice bearer path and includesnetwork elements that may switch other types of voice channels,including the routing of data packets in a data packet network. Thus,switching element 102 may comprise a router in an IP network.

Initially, switching element 102 engages in call setup with an externalnetwork element and either receives or transmits call setup signaling200. For exemplary purposes, the example will illustrate call setupsignaling 200 being received from an external network element. Afterreceiving call setup signaling 200, and performing known steps ofestablishing a call, a voice path is established between the externalnetwork element and the called party, which here is MS 150. As is shown,therefore, a voice path 202 is conducted through base station 104 to MS150. At a time prior to, or subsequent to, the voice path 202 beingcreated to MS 150, a first wireless headset communication link 204 isestablished between MS 150 and wireless headset 152. In the describedembodiment, first wireless headset communication link 204 is a Bluetoothprotocol communication link. Thus, communication signals, and morespecifically, voice that is conducted along voice path 202 istransmitted between MS 150 and wireless headset 152 over first wirelessheadset communication link 204. Some time thereafter, in the describedexample, the mobile station is docked in a docking station base unit,such as base unit 114. In the example, the docking of the mobile stationis shown at 206. Responsive to the mobile station being docked, MS 150generates call setup signals 208 to base station 104 which, in turn,generates call setup signals 210 to switching element 102. Switchingelement 102 then generates call setup signals 212 to PSTN 112 whichresponds by generating additional call setup signals 214 to base unit114. Either before these steps or subsequent to these steps, a secondwireless headset communication link 216 is established between base unit114 and wireless headset 152. Thereafter, once voice path resources havebeen reserved or allocated for a call through PSTN 112 to base unit 114,the call setup is complete. Accordingly, base unit 114 generates a callsetup complete signal 218 which is transmitted to wireless headset 152or, alternatively, to MS 150. Thereafter, the first wireless headsetcommunication link 204 may be terminated as shown at 220. In thedescribed embodiment of FIG. 5, the call setup complete signal 218 isproduced to wireless headset 152 which facilitates the wireless headset152 generating a switch command 222 to switching element 102.Approximately at the same time, meaning either prior to or subsequent tothe described signaling, a second voice path 224 is established frombase unit 114 through switching element 102 to the external networkelement. As such, the voice path has been switched from voice path 202to voice path 224 and is carried through second wireless headsetcommunication link 216 instead of first wireless headset communicationlink 204. Alternatively, as described before, an alternate embodiment ofthe invention includes MS 150 effecting the switch from the first voicepath 202 to the second voice path 224. Accordingly, in that embodiment,the call setup complete signal 218 is transmitted from base unit 114 toMS 150 which generates switch command 222 to switching element 102.Thereafter, either wireless headset 152 or MS 150 transmits a signal 220to initiate the tear-down of the first wireless headset communicationlink 204.

FIG. 6 is a flowchart illustrating a method according to one embodimentof the present invention. Initially, in a communication network, a firstvoice path is established through at least one switching element (step250). This voice path, in a telephone network, might be referred to as avoice bearer path and is between a calling party and a called party. Forthe purposes of the present invention, at least one of the calling partyand the called party is communicating with a mobile station as theinvention relates to hand-off of a wireless headset that is operativelycoupled to a mobile station once the mobile station is docked. Alongthese lines, the embodiments of the invention contemplate a Bluetoothradio associated with the docking station to facilitate a voice paththrough the cellular network being switched to the public switchedtelephone network and terminated at the docking station or base unitwherein a wireless headset communication link between the mobile stationand the wireless headset is switched to be between the base unit and thewireless headset, and more particularly, between the front end radioassociated with the base unit. Thus, an additional step of the presentembodiment of the invention, is to establish a first wireless headsetcommunication link (step 252) between the wireless headset and themobile station. While the call is active, the embodiments of theinvention provide for a hand-off from a first voice path to a secondvoice path in response to the mobile station being docked. Therefore,after the mobile station is docked, the embodiment of the inventionincludes the mobile station transmitting call setup signals to anassociated base station (step 254). Within the network, additional callsetup signaling is performed to establish a call with a specifiedlandline docking station base unit (step 256). The specified landlinedocking station base unit is identified by a phone number, in thedescribed embodiment of the invention, and a call is set up to thatlandline base unit as if a call were originally being placed to thatbase unit.

Additionally, before hand-off can occur, the wireless headset must havea wireless headset communication link established between itself and thespecified landline docking station base unit, or radio front endassociated therewith (step 258). Thus, once resources have beenallocated for the second voice path, and in a telephone network, asecond voice bearer path, and the second wireless headset communicationlink has been established, the embodiment of the invention includesswitching from the first voice path to the second voice path (step 260).In one embodiment of the invention, the mobile station generates asignal to trigger a switching element to switch from the first voicepath to the second voice path. In an alternate embodiment of theinvention, the wireless headset generates an indication to the mobilestation to prompt the mobile station to generate a signal to theswitching element to prompt the switching element to switch from thefirst voice path to the second voice path. Finally, according to oneembodiment of the invention, the first wireless headset communicationlink is terminated (step 262). Either the wireless headset or the mobilestation or the specified landline docking station base unit maydetermine to terminate the first wireless headset communication linkafter switching from the first voice path to the second voice path.

In an embodiment of the invention where the first and second wirelessheadset communication links operate according to Bluetooth protocolrequirements, one of the wireless headset, mobile station, and specifiedlandline docking station base unit, must operate as a master, while theothers operate as a slave in a piconet of the three devices.Accordingly, one aspect of the present invention contemplates the mobilestation switching master/slave roles with one of the wireless headsetand the specified landline docking station base unit as a part of thedescribed methods. That way, if the mobile station is dropped from thepiconet, one of the remaining devices may control the piconet as aBluetooth master. In the described embodiment of the invention, theBluetooth master determines when to terminate the first wireless headsetcommunication link between the wireless headset and the mobile station.In the case where the wireless headset operates as the master of thepiconet, after receiving an indication that the mobile station has beendocked, the wireless headset prompts the specified landline dockingstation base unit to become master of the piconet to enable thespecified landline docking station base unit to drop the mobile stationfrom the piconet after the second voice bearer path is established.Alternatively, in an embodiment where the wireless headset includesassociated logic to control the piconet in relation to the describedembodiments of the invention, the wireless headset determines when todrop the first wireless headset communication link with the mobilestation.

FIG. 7 is a flowchart illustrating one embodiment of the presentinvention. Initially, in a communication network, a voice path iscreated to a wireless mobile station. For a mobile station that includesa second radio front end that is operable to establish a communicationlink with a wireless headset, the embodiment of the present inventionincludes establishing a first wireless headset communication link (step270). Subsequently, the embodiment of the invention includes detectingthat the wireless telephone has been docked (step 272). In oneembodiment of the invention, as described above, the wireless telephonemay be a mobile station in a cellular network. Alternatively, however,the wireless telephone may be a wireless telephone in a wireless localarea network, a wireless telephone in a PBX network, etc. Thus, in moregeneral terms, step 272 includes detecting that the wireless telephoneof whatever type has been docked. Thereafter, the invention contemplatesestablishing a second wireless headset communication link between thewireless headset and the base unit (step 274). Either prior to orsubsequent to, the invention also includes prompting one of the landlinebase unit or the wireless telephone to establish a parallel call betweenthe landline base unit and the called terminal, namely, the wirelesstelephone (step 276). Thereafter, once the network has switched to asecond voice path, the method includes transmitting voice over thesecond wireless headset communication link between the landline baseunit and the wireless headset (step 278). Finally, the method includesterminating the first wireless headset communication link with thewireless telephone (step 280). In one embodiment of the invention, thewireless headset is operable to prompt the wireless telephone toestablish the parallel call based upon receiving an indication that thewireless telephone has been docked. Additionally, the wireless headsetis operable to prompt the wireless telephone to terminate the callbetween the service and wireless telephone and the wireless networkafter establishing the second wireless headset communication link.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof have been shown by wayof example in the drawings and detailed description. It should beunderstood, however, that the drawings and detailed description theretoare not intended to limit the invention to the particular formdisclosed, but, on the contrary, the invention is to cover allmodifications, equivalents and alternatives falling within the spiritand scope of the present invention as defined by the claims. Forexample, any known telephone protocol may be utilized for establishingany of the described telephone links. For example, mobile station maycomprise logic for establishing a first data context for carrying Voiceover IP calls by way of the first radio front end and for establishing asecond data context through the second radio front end. Similarly, thelandline docking station base unit may comprise logic for establishing adata context for carrying Voice over IP calls (for the described voicepaths herein). As may be seen, therefore, the described embodiments maybe modified in many different ways without departing from the scope orteachings of the invention.

1. A method of call setup and handoff in a communication path thatincludes at least one mobile station, comprising: establishing a firstvoice bearer path through at least one switching element between acalling party and a called party in a first communication networkaccording to a first communication protocol wherein at least one of thecalled and calling parties is communicating with a mobile station;establishing a first wireless headset communication link between themobile station that communicates over the first communication networkaccording to the first communication protocol and a wireless headsetunit; while the call is active, transmitting call setup signals from themobile station to an associated docking station base unit in response tothe mobile station being docked in the docking station base unit; withinthe first communication network, performing call setup signaling toestablish a call with docking station base unit from the switchingelement through a second communication network that communicatesaccording to a second communication protocol that is different from thefirst communication protocol and allocating resources for a second voicebearer path between the at least one switching element and the specifiedlandline docking station base unit through the second communicationnetwork; establishing a second wireless headset communication linkbetween the wireless headset unit and the specified landline dockingstation base unit; upon receiving an indication that a communicationlink has been established with the specified landline docking stationbase unit, while the wireless headset communication link with the mobilestation is established, switching, in the at least one switchingelement, the first voice bearer path from the mobile station to theallocated resources for the second voice bearer path to establish aconnection to the specified landline docking station base unit by way ofthe second voice bearer path; and terminating the first wireless headsetcommunication link.
 2. The method of claim 1 further including, prior toswitching from the first voice bearer path to the resources allocatedfor the second voice bearer path, establishing a piconet having amaster/slave relationship between the wireless headset unit, the mobilestation and the specified landline docking station base unit.
 3. Themethod of claim 2 wherein the mobile station initially operates as aBluetooth master and subsequently prompts the specified landline dockingstation base unit to become the master of the piconet.
 4. The method ofclaim 2 wherein the wireless headset unit, operating as the master ofthe piconet, drops the first wireless headset communication link withthe mobile station after establishing the second wireless headsetcommunication link with the specified landline docking station base unitand after receiving an indication that switching to the resourcesallocated for the second voice bearer path has occurred.
 5. The methodof claim 2 wherein the wireless headset unit, operating as the master ofthe piconet, receives an indication that the mobile station has beendocked and, after a piconet with the specified landline docking stationbase unit is established, prompts the specified landline docking stationbase unit to become master of the piconet to enable the specifiedlandline docking station base unit to drop the mobile station from thepiconet after the second voice bearer path is established.
 6. The methodof claim 1 wherein the wireless headset unit is operable to receive anindication from the mobile station that the mobile station has beendocked and, based upon the indication, to generate a command to themobile station to initiate a call transfer to the specified landlinedocking station base unit and further to establish a communication linkwith the specified landline docking station base unit whereby, when avoice path is switched from the mobile station to the specified landlinedocking station base unit, the wireless headset unit carries voicecommunications with the specified landline docking station base unitinstead of with the mobile station.
 7. A wireless mobile station,comprising: first radio front end for communicating over a cellularcommunication link with a cellular base station; second radio front endfor communicating over one of a wireless local area network protocol ora personal area network protocol with a wireless headset; a basebandprocessor coupled to the first and second radio front ends to produceoutgoing communication signals to the first and second front ends and toreceive and process ingoing communication signals from the first andsecond front ends; processing logic for controlling communicationsthrough the first and second radio front ends wherein the wirelessmobile station is operable, while maintaining communication linksthrough both the first and second radio front ends and while maintaininga call over a first voice bearer path according to a first communicationprotocol by way of the first radio front end, to determine that thewireless mobile station has been docked and, responsive thereto, togenerate call setup signals through the first radio front end toinitiate a call to a specified landline docking station base unitaccording to a second communication protocol; and wherein the wirelessmobile station is operable to disconnect the call from the first bearerpath after connecting to the call through a second bearer path thatincludes the specified landline docking station base unit.
 8. Thewireless mobile station of claim 7 wherein the wireless mobile stationis operable to, while acting as a personal area network master on apiconet, establish a communication link with the specified landlinedocking station base unit through the second radio front end.
 9. Thewireless mobile station of claim 8 wherein the wireless mobile stationis further operable to switch master/slave roles with one of thewireless headset or the specified landline docking station base unit.10. The wireless mobile station of claim 9 wherein the wireless mobilestation is operable to generate a transition ready signal fortransmission to a switching element by way of the first radio front endto prompt the switching element to switch to a voice bearer path to thespecified landline docking station base unit and to terminate a voicebearer path to the wireless mobile station and further wherein themobile station does not transmit the transition ready signal until afterthe communication link has been established between the specifiedlandline docking station base unit and the wireless headset through thesecond radio front end.
 11. The wireless mobile station of claim 8wherein the wireless mobile station generates call setup signals to aspecified called party number stored within memory of the wirelessmobile station which specified number is a called party number of thespecified landline docking station base unit.
 12. The wireless mobilestation of claim 8 wherein the wireless mobile station is operable tocommunicate over the first radio front end according to one of NorthAmerican TDMA, CDMA, GSM or EDGE cellular communication standards. 13.The wireless mobile station of claim 8 wherein the wireless mobilestation is operable to communicate over the second radio front endaccording to one of a Bluetooth personal area network communicationprotocol or an 802.11 based WLAN standard protocol.
 14. A wirelessmobile station, comprising: first radio front end for communicatingaccording to a cellular communication protocol; second radio front endfor communicating according to a Bluetooth protocol; a basebandprocessor coupled to the first and second radio front ends; logic forexchanging first call setup signals between the first radio front endand a wireless base station; logic for establishing a first Bluetoothcommunication link between the second radio front end and a wirelessheadset; logic for initiating a call transfer to prompt a communicationnetwork element to transfer the call from the first radio front end to aspecified landline docking station base unit; logic for establishing asecond Bluetooth voice communication link between the second radio frontend and the specified landline docking station base unit thatcommunicates according to a communication protocol that is differentfrom the cellular communication protocol; and logic for switchingmaster/slave roles with one of a wireless headset or the specifiedlandline docking station base unit to switch the wireless mobile stationinto a Bluetooth slave role.
 15. The wireless mobile station of claim 14wherein the wireless mobile station initiates the call transfer upondetermining that the wireless mobile station has been docked.
 16. Thewireless mobile station of claim 14 wherein the wireless mobile stationgenerates a transition ready signal to prompt network switching of avoice bearer path from the wireless mobile station to the specifiedlandline docking station base unit.
 17. The wireless mobile station ofclaim 14 wherein the wireless mobile station generates the transitionready signal only after the second Bluetooth voice communication linkhas been established and after a Bluetooth communication link has beencreated between the wireless headset and the specified landline dockingstation base unit.
 18. The wireless mobile station of claim 17 whereinthe wireless mobile station generates the transition ready signal onlyafter the specified landline docking station base unit and the wirelessmobile station have exchanged master/slave roles to make the specifiedlandline docking station base unit the master.
 19. The wireless mobilestation of claim 14 further including logic for establishing a firstdata context for carrying Voice over IP calls by way of the first radiofront end and for establishing a second data context through the secondradio front end.
 20. A method of servicing a voice communication andmore specifically for establishing a call between a servicing wirelesstelephone and a called terminal via a servicing wireless network,comprising: establishing a first wireless headset communication linkbetween the servicing wireless cellular telephone that communicatesaccording to a cellular protocol and a wireless headset unit; detectingthat the servicing wireless telephone has been docked; establishing asecond wireless headset communication link between the wireless headsetunit and a paired landline base unit that communicates according to acommunication protocol that is different from the cellular communicationprotocol; establishing a parallel call between the paired landline baseunit and the called terminal; and terminating the call between theservicing wireless telephone and the called terminal.
 21. The method ofclaim 20 wherein the wireless headset unit is operable to prompt amobile station to establish the parallel call based upon receiving anindication that the mobile station has been docked.
 22. The method ofclaim 20 wherein the wireless headset unit is operable to prompt themobile station to terminate the call between the servicing wirelesstelephone and the called terminal via the servicing wireless networkafter establishing the second wireless headset communication link.